Machine for knitting a tubular cover over a hose



April 1, 9 R. D. FAIGENBAUM ET AL 3,435,635

MACHINE FOR KNITTING A TUBULAR COVER OVER A HOSE Filed Jan. 28, 1966 Fl F2 F3 F4 F5 F6 F7 F8 Yl Y2 Y3 Y4 Y5 Y6 Y7 Y8 NI N2 N3 N4 N5 1N6 c| c2 c3 c4 05 06 c7 cs CI FIG -3- swxx ROY D. FAIGENBAUM JOHN J. GRECZIN United States Patent 3,435,635 MACHHWE FOR KNITTING A TUBULAR COVER OVER A HOSE Roy D. Faigenbaum, Melrose Park, and John Greczin, Philadelphia, Pa., assignors to Knitting Machinery Corp. of America, Philadelphia, Pa., a corporation Filed Jan. 28, 1966, Ser. No. 526,675 Int. Cl. D04b 9/44 US. Cl. 669 3 Claims ABSTRACT OF THE DISCLOSURE A machine for knitting a tubular fabric over a hose which will not unravel, said machine having a pre-determined number of yarn feeds and the same number of knitting cams, but a lesser number of needles. A spacer sleeve is provided within a hollow needle stem of the machine to enlarge the width of the stitches of the fabric formed on the hose.

Our invention relates to the art of knitting a tubular cover'over a hose for reinforcing the same.

More specifically, our invention relates to a machine for, and method of, knitting a tubular cover of the type disclosed in Dauphinais Patent No. 2,752,952 of July 3, 1956.

The Dauphinais patent discloses a method of knitting a tube with large stitches by providing the needle cylinder with wide grooves and by using wide needles, as shown in FIGS. 2 and 5 or by using a number of conventional width needles in each of said grooves and operating them as one, as shown in FIG. 3.

The Dauphinais patent shows a machine having six wide needle grooves with 6 wide needles, one for each groove, or three conventional width needles in each of the six grooves. For clarity and contrast, this invention will be described as embodied in a knitting machine having six, conventional width needles operating in six grooves. By conventional-width needles, we mean needles ,5 wide or thereabouts. By wide needles, we mean needles having a width equal to two or more needles.

The use of a wide needle is undesirable because it necessitates the use of cylinders having special wide grooves; because the heavy latch of the needle often fails to operate properly, and because the weight of the latch exerted undue pull on the yarn. The use of three conventional width needles in each groove is undesirable because it multiplies the risk of failure due to misalignment, or breakage; by a factor of three.

A tubular fabric of the type referred to, is preferably formed of large stitches and it must not ravel.

It is therefore the object of this invention to produce an improved method and apparatus whereby a tubular cover which will not unravel can be knit of large stitches with the use of a conventional needle cylinder having six conventional width grooves and a single conventional width needle in each groove. The reference to six grooves is only by way of example and is not critical.

The full nature of the invention will be understood from the following specification and the accompanying drawings in which:

FIG. 1 is a fragmentary vertical sectional view taken in the vicinity of the knitting line of a circular knitting machine embodying our invention.

FIG. 2 is an enlarged fragmentary elevational view showing a piece of tubular cover knit of large stitches over a piece of hose.

FIG. 3 is a developed view of the knitting cams and the relation thereof to the knitting needles.

Patented Apr. 1, 1969 In the drawings, there is shown the upper portion of the needle stem 10 of a conventional circular knitting machine against which the upper portions 12 of conventional width knitting needles 14 reciprocate. The needle cylinder, the needle bars, the hold-down ring, the cam core, and other details, are conventional, and are therefore not shown nor described herein. It is sufiicient to say that, as in the Dauphinais patent, the needle cylinder is stationary, the needles reciprocate vertically in grooves in the surface of the cylinder, the cam ring rotates to raise and lower the needles, and the spider which carries the yarn bobbins rotates about the vertical axis of the cylinder.

According to our invention, we use a single, conventional width knitting needle in each of six conventional width equally spaced grooves, not shown. Also according to this invention, we use eight conventional knitting cams which act on the butts of the six needles. By conventional width, we mean to distinguish from the wide needle of Dauphinais, the width of which equals the width of three conventional needles.

In order to produce large stitches S without the use of wide needles, or more than one conventional needle in each groove, we insert an adapter or spacer sleeve 16, the inside diameter of which is large enough to receive the hose 18. The thickness of the wall of the spacer sleeve varies according to the desired width of the stitches to be knit. By this arrangement, the Width of the stitch, that is, the distance between the sides of the stitch which extend lengthwise of the hose 18 will be a function of the distance between the outside diameter of the needle stem 10 and the inside diameter of spacer sleeve 16 measured at the knitting line 20. We are not sure why or how this happens but our best explanation at this time is that the effect described is due to the fact that as a stitch is formed on the surface of hose 18, the needles pull the yarn for making the next stitch downwardly at the knitting line 20 which is spaced from the outer surface of the hose by the thickness of sleeve 16. Be that as it may, the fact remains that, with only one conventional needle, we produce stitches as large as those produced by the wide needle of Dauphinais. These stitches are shown about full size in the drawings. In order to tighten the stitches about the hose, we increase the tension on the yarns to a point which will compel the needles forming new stitches, such as needles N5 and N2 to pull the loose yarn from the previously completed stitch before pulling yarn down through the corresponding feed. The mechanical means by which the yarn tension is regulated is well known and, not being claimed, per se, it is not shown nor described. It will be noted that tightening the stitches about the hose does not materially aflFect the shape or size of the stitch. It follows that, by varying the thickness of the wall of the spacer sleeve 16 and/or needle stem, the width of the stitch can be correspondingly varied.

To knit tubular covers of the same size stitch, on hoses of ditferent diameters, knitting heads of different sizes may be used and to knit stitches of different sizes on the same diameter hose, the thickness of the wall of the spacer sleeve will be varied. It will be noted that, by the arrangement thus far described, the size of the hose which can be covered and the size of the stitch can both be varied by merely varying the spacer sleeve or the knitting head, or both, and without otherwise disturbing the conventional number and size of the needle grooves. As shown in the drawings, sleeve 16 is of a uniform cylindrical cross section with its inner and outer surfaces concentric.

In the prior art, the size of the grooves must be varied according to the size of the single, wide needle and according to the greater, or smaller, number of small needles to be used in each groove.

As far as we are aware, the number of needles has never been less than the number of knitting cams, as distinguished from auxiliary or pattern cams, which are used for marking, tucking, or for producing other effects.

According to our invention, which is diagrammatically illustrated in FIG. 3, we use eight cams C1 through C8; eight yarn feeds F1 through F8, for feeding eight different yarns Y1 through Y8, and six needles N1 through N6. The cams and needles are so arranged that with the cams moving from right to left, as viewed in FIG. 3, only two diametrically opposed needles, such as needles N3 and N6 will be raised to their upper-yarn receiving position by cams C4 and C8 passing therebelow; that another pair of diametrically opposed needles, such as needles N2 and N will be in their lower knitting position, and another pair of diametrically opposed needles N1 and N4 will be moving up to receive fresh yarns Y1 and Y5 after having cast off the previously formed stitches.

If, at the beginning of the knitting operation, it is assumed that the needles, and yarn feeds are as shown in the following chart:

Revolutions of the yarn bobbin Feed supporting spider 1 2 3 4 5 6 7 8 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 N2 N3 N4 N5 N6 N1 N2 N4 N5 N6 N1 N2 N3 N4 1136 N1 N2 N3 N4 N5 N6 2 C2 C3 C4 C5 C6 C7 C8 It follows that during the first revolution of the spider, needles N1 through N6 will knit yarns Y1 through Y6 which are derived from feeds F1 through F6, respectively. But because there are six needles, eight cams, and eight feeds, needles N1 and N2 will also knit yarns Y7 and Y8, respectively, which are derived from feeds F7 and F8. During the second revolution of the spider, needles N3, N4, N5, N6, N1 and N2 will knit yarns Y1 through Y6 respectively, and needles N3 and N4 will also knit yarns Y7 and Y8. In the third revolution of the spider, needles N5, N6, N1, N2, N3 and N4 will knit yarns Y1 through Y6, respectively, and needles N5 and N6 will also knit yarns Y7 and Y8. At the beginning of the fourth revolution of the spider, needles N1 and N2 will again draw yarn from feeds F1 and F2 to begin a new cycle. This constant shifting means that two of the six needles will knit twice during each revolution of the spider and that each of said needles knits yarns from different feeds. This also means that the fabric thus produced can only be ravelled until the stitch made of yarn Y7 in the first revolution is reached, or until the stitch made of yarn Y5 in the second revolution is reached, or, until the stitch formed of yarn Y3 in the third revolution is reached, and so on. For practical purposes, a fabric so produced can be considered as ravel-proof.

In the foregoing disclosure, we have referred to six needles, eight yarn feeds, and eight cams, because this happens to be the number used in a successfully-operated machine. As far as we presently know, the number of needles and cams and yarn feeds may be varied as long as the number of cams equals the number of feeds but is more than the number of needles in this type of application, as distinguished from the knitting of ordinary stockings on multifeed circular knitting machines in which the number of needles has no relation to the number of cams or feeds.

We claim:

1. In a circular knitting machine for knitting a cover directly over a hose moving upwardly therethrough, said machine including:

a needle cylinder having grooves in the outer surface thereof,

a plurality of needles, one in each groove,

a plurality of knitting earns for vertically reciprocating said needles, and

a plurality of yarn feeds, one for each cam,

said feeds and said cams being rotatable about the axis of said cylinder, the improvement wherein,

the number of needles is less than the number of cams,

whereby each needle knits yarn from two feeds in each course to produce a ravel-proof cover.

2. In a machine for knitting a tubular cover directly over a hose moving upwardly therethrough, said machine including:

a needle cylinder having grooves in the outer surface thereof,

a plurality of knitting needles, one in each groove,

a plurality of yarn feeds rotatable about the axis of said cylinder for supplying yarn to said needles,

a plurality of knitting cams rotatable about the axis of said cylinder for reciprocating said needles in said grooves, and

a hollow needle stem through which said hose passes,

the improvement comprising a spacer sleeve located within said stem for spacing the outer surface of said hose from the stem,

said sleeve being of uniform cylindrical cross-section and its thickness being equal to the thickness of at least two of said needles, whereby each forming stitch extends from the outer surface of the hose to the outer surface of said stem to enlarge the width of the stitches formed on said hose by a factor determined by the thickness of said sleeve.

3. In a machine for knitting a tubular cover directly over a hose moving upwardly therethrough, said machine including:

a needle cylinder having grooves in the outer surface thereof,

a plurality of knitting needles, one in each groove,

a plurality of yarn feeds rotatable about the axis of said cylinder for supplying yarn to said needles,

a plurality of knitting cams rotatable about the axis of said cylinder for reciprocating said needles in said grooves,

a hollow needle stem concentric with said hose,

the improvement comprising means defining an inner cylindrical surface adjacent to, and concentric with, the hose, and

the outer surface of said needle stem being spaced from said inner surface by a distance substantially equal to the combined thickness of at least two of said needles, to enlarge the stitches formed on said hose by a factor determined 'by said distance.

References Cited UNITED STATES PATENTS 648,347 4/1900 Wardall. 2,355,019 8/ 1944 Stover. 3,257,828 6/ 1966 Greczin. 2,032,993 3/ 1936 Larkin. 2,084,770 6/ 1937 Larkin. 2,201,905 5/ 1940 Larkin. 2,3 87, 19 1 10/ 1945 Stover.

ROBERT R. MACKEY, Primary Examiner. 

